The primary endpoint of the study is to test whether there is a significant difference between persons receiving ARA 290 vs. persons receiving placebo in: glucose tolerance, evaluated by OGTT at baseline, and after 2 and 4 weeks. . The secondary endpoints of the study include effects of ARA 290 on: insulin sensitivity, evaluated by HOMA-IR (homeostasis model assessment of insulin resistance); insulin secretion, examined both by measuring the early insulin response (at 15 and 30 min) in OGTT, and using the HOMA-beta (homeostasis model assessment of beta cell function); and long-term glucose control, determined as glycosylated hemoglobin, HbA1c; assessment of serum levels of inflammatory agents, e.g. cytokine levels; serum levels of gluco-regulatory hormones, such as glucagon-like peptide-1 (GLP-1), and glucagon; and safety by registering reported adverse events, and by monitoring clinical chemistry parameters related to hematology, kidney function, liver function and lipid levels.